In order to inspect a wafer which is formed with a plurality of semiconductor devices, a prober is used as an inspection device. The prober includes a probe card facing the wafer and the probe card includes a plate-shaped base unit and a plurality of contact probes—columnar contact terminals—disposed on a surface of the base unit which faces the wafer to face electrode pads or soldering bumps of the semiconductor devices of the wafer, respectively (see, e.g., Patent Document 1).
In the prober, each contact probe of the probe card is in contact with an electrode pad or a soldering bump of the semiconductor devices and electricity is caused to flow from each contact probe to an electric circuit of a semiconductor device connected to each electrode pad or each soldering bump so as to inspect a conduction state of the electric circuit.
In order to improve wafer inspection efficiency, a wafer inspection device including a plurality of probe cards has been developed in which while a wafer is conveyed to one probe card by a transport stage, semiconductor devices of the wafer may be inspected by another probe card. In this wafer inspection device, when each wafer is brought into contact with each probe card, air in a space between the probe card and the wafer is evacuated and the wafer is sucked to the probe card by vacuum (see, e.g., Patent Document 2).
However, since rigidity of the wafer is low, the wafer may be bent when only the wafer is sucked to the probe card by vacuum. Thus, each electrode pad or each soldering bump may not be uniformly in contact with each contact probe of the probe card in some cases.
Therefore, as illustrated in FIG. 8A, it has been proposed that a chuck top 80—a thick plate member configured to place a wafer W thereon—be sucked to the probe card 81 by vacuum together with the wafer W so that the chuck top 80 suppresses the wafer W from being bent. In this case, the space between the chuck top 80 and the probe card 81 is surrounded by a bellows 82—a metallic bellows structure—and the air in the space is evacuated (FIG. 8B). The bellows 82, which is compressed when the chuck top 80 approaches the probe card 81, generates a reactive force, so that the position of the chuck top 80 may be deviated from the probe card 81. In addition, even after the wafer W placed on the chuck top 80 is in contact with the probe card 81 (FIG. 8C), the position of the chuck top 80 may be deviated from the probe card 81 when the reactive force of the bellows 82 is large. When the position of the chuck top 80 is deviated from the probe card 81 as described above, each electrode pad or each soldering bump of the wafer W placed on the chuck top 80 may not be in contact with a contact probe of the probe card 81.
In connection with this, the inventors of the present application have proposed preventing occurrence of positional deviation of the chuck 80 from the probe card 81 by providing a guide member 83 protruding toward the chuck top 80 at each side of the probe card 81 so as to guide the chuck top 80, as illustrated in FIGS. 8A to 8C (see, e.g., Patent Document 2).